Variation of the Chlorophyll a Related to Sea Surface Temperature, Wind and Geostrophic Currents in the Cape Verde Region Using Satellite Data

We present a comparative analysis of satellite derived climatologies in the Cape Verde region (CV). In order to establish chlorophyll a variability, in relation to other oceanographic phenomena, a set of, relatively long (from five to eight years), time series of chlorophyll a, sea surface temperature, wind and geostrophic currents, were ensembled for the Eastern Central Atlantic (ECA). We studied seasonal and inter-annual variability of phytoplankton concentration, in relation to the rest of the variables, with a special focus in CV. We compared the situation within the archipelago with those of the surrounding marine environments, such as the North West African Upwelling (NWAU), North Atlantic Subtropical Gyre (NASTG), North Equatorial Counter Current (NECC) and Guinea Dome (GD). At the seasonal scale, CV region behaves partly as the surrounding areas, nevertheless, some autochthonous features were also found. The maximum peak of the pigment having a positive correlation with temperature is found at the end of the year for all the points in the archipelago; a less remarkable rise with negative correlation is also detected in February for points CV2 and CV4. This is behavior that none of the surrounding environments have shown. This enrichment was found to be preceded by a drastic drop in wind intensity (SW Monsoon) during summer months. The inter-annual analysis shows a tendency for decreasing of the chlorophyll a concentration.Utilizando séries temporais (entre cinco e oito anos) de dados de satélite a grande escala para a zona de Cabo Verde (CV), faz-se uma análise da variabilidade da clorofila a relacionando-a com outros parâmetros oceanográficos como a temperatura superficial do mar, o vento e as correntes geostróficas. Estuda-se a variabilidade estacional e interanual da concentração do fitoplancton em relação ao resto das variáveis comparando a situação nas águas de Cabo Verde com o ambiente marinho à volta do arquipélago como o Upwelling Nordeste Africano (NWAU), o Giro Subtropical Norte-Atlântico (NASTG), a Contra Corrente Norte-Equatorial (NECC) e o Domo da Guiné (GD). À escala estacional, a zona de Cabo Verde comporta-se como parte das regiões envolventes, no entanto, algumas características autóctonas foram também encontradas. O pico máximo do pigmento mostrando uma correlação positiva com a temperatura foi encontrado no final do ano em todos os pontos eulerianos definidos para o arquipélago; um incremento menos notável, e com uma correlação negativa, também é detectada nos pontos CV2 e CV4. Este comportamento não foi visto em nenhum dos pontos do ambiente circundante ao arquipélago. O enriquecimento no final do ano foi precedido por um drástico decréscimo na intensidade do vento (Monsão do SW) durante os meses de verão. A análise interanual mostra uma tendência para o decréscimo da concentração da clorofila a

Evaluation of a Commercial Enzyme Linked Immunosorbent Assay (ELISA) for the Determination of the Neurotoxin BMAA in Surface Waters

The neurotoxin ß-N-methylamino-L-alanine (BMAA) is suspected to play a role in Alzheimer’s disease, Parkinson’s disease and amyotrophic lateral sclerosis. Because BMAA seems to be produced by cyanobacteria, surface waters are screened for BMAA. However, reliable analysis of BMAA requires specialized and expensive equipment. In 2012, a commercial enzyme-linked immunosorbent assay (ELISA) for determination of BMAA in surface waters was released. This kit could enable fast and relatively cheap screening of surface waters for BMAA. The objective of this study was to determine whether the BMAA ELISA kit was suitable for the determination of BMAA concentrations in surface waters. We hypothesised that the recovery of spiked samples was close to 100% and that the results of unspiked sample analysis were comparable between ELISA and liquid chromatography tandem mass spectrometry (LC-MS/MS) analysis. However, we found that recovery was higher than 100% in most spiked samples, highest determined recovery was over 400%. Furthermore, the ELISA gave a positive signal for nearly each tested sample while no BMAA could be detected by LC-MS/MS. We therefore conclude that in its current state, the kit is not suitable for screening surface waters for BMAA

Transporte de aerosoles de origen desértico a diferente escala espacio-temporal. Relación con perturbaciones tropicales

Ponencia presentada en: XXX Jornadas Científicas de la AME y el IX Encuentro Hispano Luso de Meteorología celebrado en Zaragoza, del 5 al 7 de mayo de 2008

Regional differences in modelled net production and shallow remineralization in the North Atlantic subtropical gyre

© The Author(s), 2012. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Biogeosciences 9 (2012): 2831-2846, doi:10.5194/bg-9-2831-2012.We used 5-yr concomitant data of tracer distribution from the BATS (Bermuda Time-series Study) and ESTOC (European Station for Time-Series in the Ocean, Canary Islands) sites to build a 1-D tracer model conservation including horizontal advection, and then compute net production and shallow remineralization rates for both sites. Our main goal was to verify if differences in these rates are consistent with the lower export rates of particulate organic carbon observed at ESTOC. Net production rates computed below the mixed layer to 110 m from April to December for oxygen, dissolved inorganic carbon and nitrate at BATS (1.34±0.79 mol O2 m−2, −1.73±0.52 mol C m−2 and −125±36 mmol N m−2) were slightly higher for oxygen and carbon compared to ESTOC (1.03±0.62 mol O2 m−2, −1.42±0.30 mol C m−2 and −213±56 mmol N m−2), although the differences were not statistically significant. Shallow remineralization rates between 110 and 250 m computed at ESTOC (−3.9±1.0 mol O2 m−2, 1.53±0.43 mol C m−2 and 38±155 mmol N m−2) were statistically higher for oxygen compared to BATS (−1.81±0.37 mol O2 m−2, 1.52±0.30 mol C m−2 and 147±43 mmol N m−2). The lateral advective flux divergence of tracers, which was more significant at ESTOC, was responsible for the differences in estimated oxygen remineralization rates between both stations. According to these results, the differences in net production and shallow remineralization cannot fully explain the differences in the flux of sinking organic matter observed between both stations, suggesting an additional consumption of non-sinking organic matter at ESTOC.B. Mourino was supported by the Ramon y Cajal program from the Spanish Minister of Science and Technology. Funding for this study was provided by the Xunta de Galicia under the research project VARITROP (09MDS001312PR, PI B. Mourino) and by the Ministerio de Ciencia e Innovation MOMAC project (CTM2008-05914/MAR)

A Variable Stiffness Actuator Module With Favorable Mass Distribution for a Bio-inspired Biped Robot

Achieving human-like locomotion with humanoid platforms often requires the use of variable stiffness actuators (VSAs) in multi-degree-of-freedom robotic joints. VSAs possess 2 motors for the control of both stiffness and equilibrium position. Hence, they add mass and mechanical complexity to the design of humanoids. Mass distribution of the legs is an important design parameter, because it can have detrimental effects on the cost of transport. This work presents a novel VSA module, designed to be implemented in a bio-inspired humanoid robot, Binocchio, that houses all components on the same side of the actuated joint. This feature allowed to place the actuator's mass to more proximal locations with respect to the actuated joint instead of concentrating it at the joint level, creating a more favorable mass distribution in the humanoid. Besides, it also facilitated it's usage in joints with centralized multi-degree of freedom (DoF) joints instead of cascading single DoF modules. The design of the VSA module is presented, including it's integration in the multi-DoFs joints of Binocchio. Experiments validated the static characteristics of the VSA module to accurately estimate the output torque and stiffness. The dynamic responses of the driving and stiffening mechanisms are shown. Finally, experiments show the ability of the actuation system to replicate the envisioned human-like kinematic, torque and stiffness profiles for Binocchio

Teledetección de aerosoles Saharianos con fines sanitarios

Ponencia presentada en: 1er Encuentro sobre Meteorología y Atmósfera de Canarias, celebrado en el Puerto de la Cruz, los días 12,13 y 14 de noviembre de 2003. El encuentro estuvo organizado por el Centro Meteorológico Territorial en Canarias Occidental, con la colaboración del Observatorio Atmosférico de Izaña y del Grupo de Física de la Atmósfera de la Facultad de Física (Universidad de La Laguna)Utilizamos datos de satélite para estimar las frecuencias e intensidades de entradas de Calima en Canarias y emplear esa información como medida preventiva en los enfermos asmáticos. Para el período comprendido entre los años 1997-2000, se procesaron imágenes de satélite y se analizaron los datos de espesor óptico. Se obtuvieron valores característicos para la frecuencia y variación en magnitud de días con presencia de Calima , y su relación con los cambios meteorológicos y climáticos. Paralelamente se realizó un estudio estadístico con los casos de individuos atendidos de enfermedades alérgicas de tipo respiratorio en los servicios de urgencias del hospital Dr. Negrín de Gran Canaria . Los máximos de espesor óptico y el aumento en casos atendidos clínicamente coinciden en la época del año y ambos aumentan en el 2000 con respecto a años anteriores. Se concluye en que sería de gran utilidad el establecer y pronosticar un parámetro de riesgo ambiental en base a medidas de satélite

Fixed and drifting buoys around the national Spanish waters

Joint Technical Commission for Oceanography and Marine Meteorology (JCOMM) Marine Technical Conference, The Technical Conference (TECO) Toward an Integrated Met-ocean Monitoring, Forecasting and Services System, 25-29 October 2017, Geneva, SwitzerlandImproving the knowledge of the ocean and seas surrounding the Iberian Peninsula and Balearic and Canary islands is an objective of the Spanish oceanography. For that purpose, a number of fixed and drifting floats have been established in the last 25 years. Data buoys measure sea surface temperature and salinity, ocean current velocity, air temperature, humidity, wave characteristic and wind velocity across seas and ocean. The objective is increase the quantity, quality, coverage and timeliness of atmospheric and oceanographic data. These observations are used immediately to improve forecast and therefore increase marine safety. The main group of fixed buoys is formed by the Puertos del Estado deep and shallow buoy networks, but a series of well instrumented new platforms has been established in later times. The RAIA Project (Xunta de Galicia), PLOCAN, SOCIB, IEO, Euskalmet-AZTI, ICM and UTM (CSIC) and University and Polytechnic of Barcelona have completed the Observing System. Most of the buoys are transmitting data by GTS for using in atmospheric and ocean prediction models. Multidisciplinary sensors as Dissolved Oxygen, Fluorescence Chlorophyll or pCO2 has been mounted in the buoys and calibration/validation procedures has been developed for improve data quality. Antifouling systems recently developed have also been included and quality of the optical sensors measurements has improved. Drifting floats has increase its number and importance, from Argo floats to traditional deriving ones improving the Spanish contribution to IOC and WWO and JCOMM. Spain is member of EuroArgo ERIC. SOCIB and IEO are the main contributors. Also multidisciplinary work has been done associated to Argo buoys. BGQ ARGO incorporate O2 sensor. ICM, SMOS Barcelona Expert Center, and SOCIB are the main contributors to the drifting buoys group. Main objectives are improving Technological development as well as data management. Tropical and Southern Atlantic Ocean are the main studying areasPeer Reviewe

Evolving and sustaining ocean best practices and standards for the next decade

The oceans play a key role in global issues such as climate change, food security, and human health. Given their vast dimensions and internal complexity, efficient monitoring and predicting of the planet's ocean must be a collaborative effort of both regional and global scale. A first and foremost requirement for such collaborative ocean observing is the need to follow well-defined and reproducible methods across activities: from strategies for structuring observing systems, sensor deployment and usage, and the generation of data and information products, to ethical and governance aspects when executing ocean observing. To meet the urgent, planet-wide challenges we face, methods across all aspects of ocean observing should be broadly adopted by the ocean community and, where appropriate, should evolve into "Ocean Best Practices." While many groups have created best practices, they are scattered across the Web or buried in local repositories and many have yet to be digitized. To reduce this fragmentation, we introduce a new open access, permanent, digital repository of best practices documentation (oceanbestpractices.org) that is part of the Ocean Best Practices System (OBPS). The new OBPS provides an opportunity space for the centralized and coordinated improvement of ocean observing methods. The OBPS repository employs user-friendly software to significantly improve discovery and access to methods. The software includes advanced semantic technologies for search capabilities to enhance repository operations. In addition to the repository, the OBPS also includes a peer reviewed journal research topic, a forum for community discussion and a training activity for use of best practices. Together, these components serve to realize a core objective of the OBPS, which is to enable the ocean community to create superior methods for every activity in ocean observing from research to operations to applications that are agreed upon and broadly adopted across communities. Using selected ocean observing examples, we show how the OBPS supports this objective. This paper lays out a future vision of ocean best practices and how OBPS will contribute to improving ocean observing in the decade to come

Seasonal and inter-annual variability in nutrient supply in relation to mixing in the Bay of Biscay

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